Investor optimism tumbled to a level of +24, down from +40 in February, according to the latest Wells Fargo/Gallup Investor and Retirement Optimism Index. The dip was driven by rising investor pessimism about the economy. The optimism of retired respondents plummeted to +17, down from +38 in February, down from +61 a year ago. Non-retired Americans recorded an optimism level of +27 versus +41 in February.

One in three investors (33%) said low interest rates will cause them to delay retirement. Forty-five percent of non-retired Americans and 34% of retirees said they fear outliving their money in retirement because of current low interest rates. Slightly more than a quarter (26%) of non-retired and 19% of the retired said they may invest their money in ways they “might have avoided,” because of low interest rates. Thirty-two percent of investors think today’s low interest rates are likely to lead to a spike in inflation.

Three in four investors are dissatisfied with the total cost of health care. Although most respondents were satisfied with the quality of health care they receive—rating it excellent or good—a majority (80%) said health care is in “a state of crisis” or has “major problems.” Eight in 10 gave high ratings to their insurance coverage.

Rising health insurance costs also cause alarm. In the past year, two in three investors (67%) said their insurance costs increased a lot (23%) or a little (44%). Almost one-third of investors (29%) said rising health care costs have reduced their ability to save for retirement and forced some (12%) to delay retirement.